The state regulates flood-prone lands and waters to prevent and alleviate flooding threats to life and health and reduce private and public economic losses. The purpose of 76-5 MCA, parts 1-4 is to manage and guide the development of state floodway areas and to coordinate federal, state, and local management activities.

Under this statute, the Department of Natural Resources and Conservation will survey and designate flood plains and floodways for each watercourse and drainway in the state. The Department will also set minimum standards for use and development of floodplains and floodways. Upon receipt of the survey information, local governments are responsible for setting land use regulations that meet or exceed the standards set by the Department. Some open-space uses are allowed within designated areas, but permits from the Department are required for other projects, including the construction of structures. Additionally, the following uses are prohibited within designated floodways:

(1) a building for living purposes or place of assembly or permanent use by human beings;
(2) a structure or excavation that will cause water to be diverted from the established floodway, cause erosion, obstruct the natural flow of water, or reduce the carrying capacity of the floodway;
(3) the construction or permanent storage of an object subject to flotation or movement during flood level periods.

Some exemptions apply (see section 76-5-4). Local governments may adopt the authority to issue permits by petitioning the Department.

The purpose of 76-5 MCA, part 11 is to describe the water conservation and flood control projects that may be initiated by local and municipal governments.